Image reading apparatus

Abstract

An image reading apparatus comprises a reading unit including a sensor; a driving unit configured to move the reading unit to read an original placed on a platen; a feed unit configured to feed the original to move and read the original with respect to the reading unit being at rest in a predetermined position; a transfer unit configured to transfer a driving force of the driving unit to the feed unit while the reading unit is at rest in the predetermined position; and a switching unit configured to permit or restrict movement of the reading unit from the predetermined position.

What is claimed is: 
     
         1 . An image reading apparatus comprising:
 a reading unit including a sensor;   a driving unit configured to move said reading unit to read an original placed on a platen;   a feed unit configured to feed the original to move and read the original with respect to said reading unit being at rest in a predetermined position;   a transfer unit configured to transfer a driving force of said driving unit to said feed unit while said reading unit is at rest in the predetermined position; and   a switching unit configured to permit or restrict movement of said reading unit from the predetermined position.   
     
     
         2 . The apparatus according to  claim 1 , wherein a driving source of said driving unit is mounted on said reading unit, and moves together with said reading unit. 
     
     
         3 . The apparatus according to  claim 1 , wherein said switching unit performs switching upon movement of said reading unit. 
     
     
         4 . The apparatus according to  claim 1 , wherein
 said switching unit comprises:
 a switch member configured to ascend or descend upon movement of said reading unit; 
 a rotor configured to rotate through a predetermined angle every time said switch member ascends or descends, and contact a projection formed on said reading unit; 
 a stator configured to rotatably support said rotor; and 
 a biasing unit configured to bias said switch member and said rotor in one direction, 
 said reading unit including a pressing portion in which said reading unit engages with said switch member in accordance with a position thereof. 
   
     
     
         5 . The apparatus according to  claim 4 , wherein
 a pair of switching units are disposed on said reading unit, and said pressing portion is formed on said reading unit at a position corresponding to each of said pair of switching units, and   said switching unit performs switching upon movement of said reading unit.   
     
     
         6 . The apparatus according to  claim 1 , wherein said reading unit reads an original moved by said feed unit when said reading unit is at the predetermined position. 
     
     
         7 . An image reading apparatus comprising:
 a reading unit including a sensor;   a driving unit which is configured to move said reading unit to read an original placed on a platen, and includes a driving source mounted on said reading unit;   a feed unit configured to feed the original to move and read the original with respect to said reading unit being at rest in a predetermined position; and   a transfer unit configured to transfer a driving force of said driving unit to said feed unit while said reading unit is at rest in the predetermined position.   
     
     
         8 . The apparatus according to  claim 7 , further comprising:
 a unit configured to restrict movement of said reading unit so that said reading unit rests at the predetermined position even when said driving source is driven.